At MasTec, it doesn’t seem like the U.S. economy is in the doldrums.

The Coral Gables-based infrastructure construction company is building a wind farm in Texas and gas pipelines in Nevada and Canada, installing communications lines in Las Vegas and maintaining an electric transmission line in New York state.

The firm employs about 12,220 people, up from 9,400 at the end of last year and 8,400 at the close of 2009.

Profits up

MasTec’s revenues during the first three quarters of 2011 rose 42 percent to $2.2 billion, compared to about $1.6 billion for the same period in 2010. For the same time periods, the company’s net profits were $97.4 million, up more than 87 percent from $52 million.

MasTec also reported that its work backlog had reached a record high $3.1 billion as of Sept. 30, 2011, compared to $2.3 billion at the end of the third quarter last year. The $3.1 billion does not include a $300 million contract awarded MasTec that has yet to receive final financing approval.

What going on? To begin with, MasTec’s existing businesses have expanded. “We grew in every sector of our business except renewables,” said José R. Mas, MasTec president and CEO.

Growth in wireless, Mas said, “has been astronomical.” When the company began building wireless networks several years ago, revenues for the first year were $70 million, the MasTec CEO said. Now, revenues from wireless contracts are around $600 million.

AT&T Wireless and DirecTV are the company’s two largest customers, each accounting for about 20 percent of revenues, and they are expanding despite the slow economy. MasTec also has contracts with a range of other companies in different sectors, as well as with federal and regional government agencies.

Moreover, MasTec continued its strategy of acquiring businesses that expand its geographic reach and add new clients and revenue. For example, at the end of last year MasTec bought 33 percent of EC Source Services, an Arizona-based contractor specializing in extra-high voltage transmission lines, and in 2011 acquired the remaining 67 percent of the company. This year MasTec also bought Halstead Communications to expand its installation of DirecTV in parts of New York, Pennsylvania and New England, and acquired a Canadian energy infrastructure firm, Fabcor.

But even as MasTec expects strong growth to continue in all its business sectors and foresees an expansion in renewable energy projects next year, the company faces challenges. Its stock price has fallen 24 percent since Nov. 1.

Managing rapid demand growth in areas like wireless has increased expenses, Mas said. “We are worried about meeting demand for our customers and we go all out to get the work done,” he said. To achieve this, the company adds new employees, who require a training period before they are fully productive, thus increasing costs.

The company also lowered its earnings per share projection for the fourth quarter of 2011, noting that heavy rains have slowed down construction work on a major gas pipeline MasTec is building to move natural gas from the Marcellus Shale, a large formation of sedimentary rocks located in six eastern states. When the ground is wet, trenches cut for the pipeline collapse and construction cannot proceed. If the ground freezes, work could continue but so far the region has not had sustained cold weather.

Renewable energy

In addition, MasTec is expected to sell a unit called DirectStar next year, a move that will impact revenues.

As for renewable energy, Mas said the company has built up a backlog of contracts for renewable projects and he expects 2012 to be the company’s biggest year for this sector.

Recent reports by stock analysts said MasTec has good long-term prospects despite problems it faced this quarter. “CEO José Mas’ commentary at a recent analyst dinner supports our thesis that MasTec’s powerful growth outlook remains intact and that the recent pullback [in share prices] represents a very attractive entry point,” said Stifel Nicolaus in a company update that went on to call MasTec its “top idea in the infrastructure space.” The firm assigned a buy rating to MasTec, as did Key Banc Capital Markets. Credit Suisse and FBR Capital Markets gave MasTec an outperform rating and Barclays Capital assigned an overweight rating.

In its compilation of analyst recommendations, Thomson/First Call this month posted three strong buys, six buys, three holds and no underperform or sell ratings for MasTec shares.

The U.S. economy “is working its way out of a rut,” Mas said in an interview. “It’s getting marginally better but it’s still a very difficult market,” he added.

“At MasTec, we had a great year in 2010 and we’re having a better 2011. We’re in a position to have a great 2012.”